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ABSTRACTMapping closely to how ore deposit geology is now taught, this textbook systematically describes and illustrates the major ore deposit types, linking this to their settings in the crust and the geological factors behind their formation. Written for advanced undergraduate and graduate students with a basic background in the geosciences, it provides a balance of practical information and coverage of the relevant geological sciences, including petrological, geochemical, hydrological and tectonic processes. Important theory is summarized without unnecessary detail and integrated with students' learning in other topics, including magmatic processes and sedimentary geology, enabling students to make links across the geosciences. Students are supported by further reading, a comprehensive glossary, and problems and review questions that test the application of theoretical approaches and encourage students to use what they have learnt. A website includes visual resources and combines with the book to provide students and instructors with a complete learning package."

"A large portion of southern palawan is underlain by ultramafic rocks that have undergone weathering with the residual formation of nickeliferous laterite...."

"Studi geologi dan geokimia tanah dilakukan untuk menentukan potensi dan prospek mineralisasi bijih di Daerah “X”, Sulawesi Utara sebagai salah satu daerah yang berpotensial mengandung mineralisasi logam ekonomis. Penelitian dilakukan dengan mengintegrasikan data geologi dan data pemercontohan tanah (oil sampling) oleh PSDMBP yang masih perlu diolah secara geostatistik. Studi geologi dilakukan melalui integrasi terhadap data sekunder dari PSDMBP dengan analisis geomorfologi, kelurusan, dan petrografi untuk menentukan kondisi geomorfologi, litologi, struktur, zona alterasi, serta kelurusan urat kuarsa. Analisis geostatistik dilakukan dengan analisis univariat dan multivariat untuk menentukan persebaran anomali unsur dan asosiasi antar unsur. Hasil penelitian menunjukkan bahwa daerah penelitian memiliki satuan geomorfologi berupa satuan perbukitan tinggi vulkanik berlereng curam dan satuan perbukitan vulkanik berlereng agak curam-curam. Litologinya terdiri atas satuan dasit, satuan andesit, satuan tuff, dan satuan batupasir dengan struktur geologi berupa pola kelurusan dengan orientasi barat laut – tenggara. Zona alterasi pada daerah penelitian meliputi zona alterasi argilik (fasies kaolinit + kuarsa + ilit + ilit-smektit) dan zona alterasi propilitik (fasies klorit + illite-smektit + kalsit + epidot). Terdapat tiga jalur urat kuarsa berorientasi barat daya – timur) laut yang teridentifikasi pada daerah penelitian, yaitu Urat Kuarsa X (bagian tenggara), Urat Kuarsa Y (bagian barat), dan Urat Kuarsa Z (bagian barat laut). Hasil analisis statistik terhadap empat unsur yang dapat diteliti (Cu, Au, Sb, Hg) menunjukkan masing-masing nilai ambang sebesar 72.44 ppm, 16 ppb, 3.39 ppm, dan 551.72 ppb. Hasil analisis multivariat menunjukkan adanya satu asosiasi unsur pada daerah penelitian, yaitu Au-Sb-Hg. Persebaran anomali unsur logam bijih kemudian diketahui secara umum memiliki pengayaan disekitar urat kuarsa dan mengalami proses dispersi pada unsur Cu, Sb, dan Hg. Potensi mineralisasi bijih pada daerah penelitian berasal dari sistem endapan epitermal sulfidasi rendah dengan prospek mineralisasi sebagian besar berada pada ketiga jalur urat kuarsa dan bagian timur laut serta selatan daerah penelitian. Prospek bagian timur laut dan selatan diindikasikan sebagai kehadiran urat kuarsa di bawah permukaan yang tertutup oleh tanah dan tidak terpetakan.

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Soil geology and geochemical studies were carried out to determine the potential and prospects for ore mineralization in “X” area, North Sulawesi as one of the areas with the potential for economic metal mineralization. The research was conducted by integrating geological and soil sampling data by PSDMBP which still needed to be processed geostatistically. Geological studies was conducted through integration of secondary data from PSDMBP with geomorphological, lineaments and petrographic analyzes to determine geomorphological conditions, lithology, structure, alteration zones, and alignment of quartz veins. Geostatistic analysis was carried out using univariate and multivariate analysis to determine the distribution of elemental anomalies and associations between elements. The results showed that the study area has geomorphological units of high volcanic hill units with steep slopes and volcanic hill units with rather steep slopes. The lithology consists of dacite, andesite, tuff, and sandstone with geological structure from lineament analysis shows a northwest-southeast orientation. The alteration zones in the study area include argillic alteration zones (kaolinite + quartz + illite + illite-smectite facies) and propylitic alteration zones (chlorite + illite-smectite + calcite + epidote facies). There are three southwest-northeast oriented quartz veins identified in the study area, namely the X Quartz Vein (southeast), Y Quartz Vein (western part), and Z Quartz Vein (northwestern part). The results of the statistical analysis of the four elements that can be studied (Cu, Au, Sb, Hg) show that each threshold value is 72.44 ppm, 16 ppb, 3.39 ppm and 551.72 ppb. The results of the multivariate analysis showed that there were one elemental associations in the study area, namely Au-Sb-Hg. The distribution of anomalous metal ore elements is then known to generally have enrichment around quartz veins and undergo a dispersion process in Cu, Sb, and Hg elements. The potential for ore mineralization in the study area originates from a low sulfidation epithermal deposit system with the prospect of mineralization being mostly in the third lane of the quartz vein and the northeastern and southern parts of the study area. The prospects for the northeast and south are indicated by the presence of subsurface quartz veins that are covered by soil and are not mapped."

"Daerah prospek Anjing Hitam merupakan daerah prospek endapan mineral yang berada di Kabupaten Dairi, Provinsi Sumatra Utara. Pada daerah prospek ini terdapat endapan bijih tipe Sedimentary Exhalative (SEDEX) dengan kandungan Zn-Pb-Ag dengan keberadaan tubuh bijih sebagian besar terdapat pada Formasi Kluet yang merupakan bagian dari Grup Tapanuli. Daerah prospek Anjing Hitam berada pada wilayah konsesi tambang PT Dairi Prima Mineral dan sudah dilakukan eksplorasi dan eksploitasi. Pada tahun 2020 ditemukan adanya indikasi keterdapatan endapan bijih tipe SEDEX pada Formasi Alas yang berlokasi di Kecamatan Tanahpinem dan sekitarnya, Kabupaten Dairi. Penelitian ini bertujuan untuk mengidentifikasi dan menentukan karakteristik mineral bijih pada sampel yang diambil dari lokasi penemuan endapan bijih tipe SEDEX tersebut. Metode yang digunakan pada penelitian ini yaitu analisis makroskopis, petrografi, mineragrafi dan XRF (X-ray Fluorescence). Hasil analisis menunjukkan karakteristik endapan SEDEX Formasi Alas di daerah penelitian secara litologi terdiri dari batulanau, batupasir, batusedimen gamping dan batugamping kristalin. Bijih teramati terbentuk secara syngenetic berupa batulanau dengan tekstur banded dengan mineral bijih berupa mineral sulfida halus berupa slaferit, pirit, kalkopirit dan galena dengan keberadaan mineral sulfat berupa barit. Terdapat alterasi sericitic yang berasosiasi dengan mineralisasi berupa mineral sulfida terdiseminasi dan juga terdapat pengayaan unsur Mn pada endapan SEDEX Formasi Alas di daerah penelitian. Terdapat indikasi keterjadian supergene yang membentuk gossan pada endapan SEDEX Formasi Alas di daerah penelitian yang ditandai dengan keberadaan batulanau yang teroksidasi derajat tinggi dengan asosiasi mineral berupa hematit, goetit dan kaolinit. Endapan SEDEX Formasi Alas di daerah penelitian mengandung unsur bijih Zn Pb dan Ag. Terdapat pengayaan unsur asosiasi endapan SEDEX berupa Fe, P, Ba, As, Sn, Ga, Ni dan Sb. Berdasarkan karakteristiknya, endapan SEDEX Formasi Alas di daerah penelitian memiliki analogi yang serupa dengan endapan SEDEX pada daerah prospek Anjing Hitam dan endapan SEDEX secara garis besar yang dipublikasikan oleh USGS. Berdasarkan hasil analogi dengan model endapan SEDEX ideal, endapan SEDEX Formasi Alas di daerah penelitian memiliki karakteristik yang sesuai dengan tubuh bijih bagian distal.

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The Anjing Hitam Prospect Area is a prospec mineral deposit area located in Dairi District, North Sumatra Province. This prospect area contains Sedimentary Exhalative (SEDEX) ore deposits containing Zn-Pb with the presence of the ore body mostly in the Kluet Formation which is part of the Tapanuli Group. The Anjing Hitam prospect area is in the mining concession area of ​​PT Dairi Prima Mineral which has already been explored and exploited. In 2020, there is an indication that the presence of SEDEX-type ore deposits was found in the Alas Formation located in Tanahpinem District and its surroundings, Dairi Regency. This study aims to identify and determine the characteristics of ore minerals in samples taken from the location of the discovery of the SEDEX type ore deposit. The methods used in this research are macroscopic analysis, petrography, mineragraphy and XRF (X-ray Fluorescence). The results of the analysis show that the characteristics of the Alas Formation SEDEX deposits in the study area are lithologically composed of siltstone, sandstone, limestone sedimentary rock and crystalline limestone. The ore was observed to be syngenetically formed in the form of siltstone with a banded texture with ore minerals in the form of fine sulphide minerals such as slaferrite, pyrite, chalcopyrite and galena with the presence of sulfate minerals in the form of barite. There is sericitic alteration associated with mineralization in the form of disseminated sulfide minerals and there is also an enrichment of Mn in the SEDEX deposit of the Alas Formation in the study area. There are indications of the occurrence of a gossan-forming supergene in the SEDEX deposit of the Alas Formation in the study area which is characterized by the presence of highly oxidized siltstone with mineral associations such as hematite, goethite and kaolinite. The Alas Formation SEDEX deposit in the study area contains elements of Zn, Pb and Ag ores. There is enrichment of association elements of SEDEX deposit in the form of Fe, P, Ba, As, Sn, Ga, Ni and Sb. Based on its characteristics, the Alas Formation SEDEX deposit in the study area has a similar analogy to the SEDEX deposit in the Anjing Hitam prospect area and the general SEDEX deposit published by the USGS. Based on the results of an analogy with the ideal SEDEX deposit model, the Alas Formation SEDEX deposit in the study area has characteristics that match the distal ore body."

"Indonesia merupakan negara yang kaya akan sumber daya alam, salah satunya merupakan deposit uranium. Keterdapatan uranium di Indonesia masih merupakan hal yang jarang dijumpai sehingga dapat menjadi topik yang sangat menarik untuk dipelajari lebih lanjut. Penelitian ini bertujuan untuk mengetahui tipe deposit serta keterbentukan dari uranium yang terdapat di Desa Takandeang, Kecamatan Tapalang, Kabupaten Mamuju, Sulawesi Barat. Penelitian dimulai dengan pemetaan geologi permukaan dan radiometri dengan bantuan alat gamma surveyor (model RS 125) yang kemudian dilanjutkan dengan analisis petrologi dan petrografi, serta analisis geokimia. Berdasarkan hasil dari penelitian, diketahui bahwa batuan penyusun lapangan penelitian terdiri atas autobreksi leusitit, breksi epiklastik, lava phonolitik foidit, batupasir tufaan, dan batugamping terumbu. Data radiometri dan geokimia XRF menunjukan anomali uranium tertinggi terdapat pada autobreksi leusitit. Anomali yang terjadi pada daerah penelitian berupa rekonsentrasi unsur uranium pada batuan autobreksi yang disebabkan oleh aktivitas hidrotermal yang juga didukung tipe magma dan kontrol struktur pada daerah penelitian.

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Indonesia is rich in natural resources, one of which is a uranium deposit. In Indonesia, uranium‟s occurrence is still rarely found so it can be a very interesting topic for further study. This study aims to determine the type of deposit and the formation of uranium contained in Takandeang Village, Tapalang District, Mamuju Regency, West Sulawesi. The study began with surface geology and radiometry mapping with the help of a gamma surveyor (RS 125 model) which was continued with petrological and petrographic analysis, and geochemical analysis. Based on the results of the study, it is known that the constituent rock of the research field consists of leucitite autobreccias, epiclastic breccias, phonolytic lava phoidolytic, tuffaceous sandstones, and reef limestones. Radiometric data and XRF geochemistry show that the highest uranium anomaly is found in leucitite autobreccias. The anomaly that occurred in the study area was in the form of reconcentration of uranium elements in autobrection rocks caused by hydrothermal activity which was also supported by magma type and structural control in the study area."